Impulse repeater



Jan., 4, 1938. i F, 5, KINKEAD 2,104,426

IMPVULSE REPEATER Filed OC. 16, 1955 POLAR/IED POLAR/IED hill-JT- @yF.5.K/NKEAD A T TORNE Y Patented Jan. 4, 1938 UNITED STATES PATENTOFFICE signor to Bell Telephone Laboratories, Incorporated, New York, N.Y., a corporation of New York Application October 16, 1935 Serial No.45,170

6 Claims.

This invention relates to impulse repeaters and more particularly toimpulse repeaters for use in telegraph systems.

In large extended telegraph systems, such as used in police networks,news networks, etc., it is necessary to connect a large number ofstations by means of lines of different types together and to arrangethe various circuits so that the signal impulses transmitted from anystation will be received at all the other stations connected to thenetwork. In addition, it is necessary at times to temporarily add to thesystem various lines of different types.

In order to fulfill these requirements a repeating system has beendeveloped in which the relay equipment is associated with each line fortransmitting signal impulses between the respective lines and a commonimpulse circuit. Repeater systems of this type have been disclosed inPatent 2,056,277, granted Oct. 6, 1936, to F. S. Kinkead and G. A.Locke, Serial No. 32,866 led July 24, 1935.

In repeater systems of this type, stray impulses arising in any of thelines will disturb the transmission to and from all the other stationsand lines of the system.

The object of this invention is to provide an auxiliary circuit whichmay be inserted between the common circuit and the repeating relaysindividual to each line circuit for preventing the transmission ofmomentary stray impulses 'during the transmission of signal impulses inthe opposite direction and for recording the number of these strayimpulses received from each line.

A feature of the invention relates to the transmission of long breaksignal impulses in` all direc* tions through the repeating system at alltimes without recording these break signals as momentary stray impulses.

In accordance with the preferred embodiment of this invention, one ormore auxiliary relay circuits or repeaters are connected between thecommon circuit and` the individual line circuits for repeating impulsesbetween the common circuit and equipment connected to the line circuit.This auxiliary circuit is provided with slowacting relays which preventthe transmission of momentary short stray impulses through the circuitin a ydirection opposite to the direction of transmission of signalimpulses. Recording devices are provided to recor'd the number of theseshort stray impulses received from` the line durn ing the time impulsesare being transmitted to the line. Additional circuit arrangements`permit the transmission ofwlong breaksignal `impulses through thecircuit in both directions at all times and prevent the recording ofthese long break signal impulses as momentary stray irnpulses.

These and other objects and features of this invention may be more fullyunderstood from the followingr Idescription when read with reference tothe attached drawing in which:

Fig. l shows a general form oi a repeating system to which the inventionis applicable; and

Fig. 2 shows details of one specinc form of the auxiliary repeatingequipment which may be connected between the individual relaysassociated with any line and common impulse circuit.

Referring now to Fig. 1, a plurality of sub i,

Scribers stations II) are shown each provided with a receiving device IIsuch as the printing magnet or -line relay and a transmitting devicesuch as contacts I2. These telegraph stations II) may be of any suitabletype or class which are: connected by means of loops or lines I3 to acentral repeater point where relay and other equipment I4 is located. Atthe central repeater point, a plurality of relay equipments I4 areprovided, one of the said equipments being associated with andindividual to each of the loop circuits I3 incoming from telegraphstations I0. These equipments I4 and lines I3 may be of any suitabletype, such as represented by loop I3 which transmits signals in eitherdirection or by loops or lines, such as illustrated by lines I5 and I6,which are adapted to transmit signals in only one direction, one of thelines serving to transmit signals in one direction while the othertransmits signals in the reverse direction. These loop circuits may bearranged to transmit any desired vtype of signal impulses such ascarrier current signal impulses or low frequency telegraph signalimpulses. The equipment at each telegraph station I0, as well as the`relay and associated equipment Id. associated with the individuallines, is adapted' to transmit and receive the type of signal impulseswhich are transmitted over the interconnecting loop or line circuits.The relay equipments III are each provided with a trans- `mitting relay2| and a receiving relay 22, in

addition to thp` other relays and equipment cooperating with theincoming lines I3 from the telegraph stations E6. Relay 2| is providedto repeat signals received from the connected telegraph station IIl overthe associated line I3 to common circuit 33 while receiving relay 22 isadapted to receive signal impulses from the common circuit 33` and`repeatthese signals` to the associated telegraph station I0 through therelated equipment and line I3. Thus, when relay 2| is released by aspacing signal received from telegraph station I9, which spacing signalmay be a carrier current spacing signal, a spacing signal in a positiveand negative current impulse system, or a spacing signal in a currentand nocurrent system, it connects ground to the common circuit 33 which,in turn, causes the receiving relays 22 of the other relay equipments I4to operate and thus repeat the spacing signal to the other telegraphstations I0 connected to the other relay equipments I4.

It is thus quite apparent that any impulses originating at any of thetelegraph stations Ill connected to the system, or in any of the linesconnecting the stations to their associated equipments I4 will berepeated to all the other telegraph stations !9 connected to the system.Also, in case any stray or momentary signal impulses arise Yin any lineof the system, these impulses will be transmitted to and interfere withthe transmission between all the other stations connected to the system.In accordance with this invention, an additional relay equipment I8 isconnected between the common circuit 33 and the relay equipment I4individual to the lines connected into the system which are subjected tothese disturbances. This additional equipment prevents momentary strayimpulses arising in the line associated with this auxiliary equipment I8from interfering with the transmission between all the other telegraphstations connected to the particular telegraph system.

Details of this auxiliary relay equipment are shown in Fig. 2. Relays 23and 24 are preferably polar relays and are normally maintained in theposition shown in Fig. 2 by a biasing current flowing through the upperwindings. Relays 25 and 26 are made slow-acting in any suitable way,such as, for example, by providing them with a copper sleeve. Theremaining relays are ordinarily neutral electromagnet relays.

As shown in Figs. 1 and 2, a lead 20 is connected to the common circuit33 while lead I9 is connected to the relay equipment I4 associated withthe individual lines I3 connected to the telegraphstations I9. Whensignals are being transmitted from the common circuit 33 throughauxiliary equipment I8 and relay equipment I4 over a telegraph line I3to a station I0, ground is connected to the common circuit 33 by atransmitting relay 2| under control of another telegraph station whichis transmitting. The ground thus connected to lead 20 of Fig. 2 throughthe common circuit 33 causes a current to ow 'through the armature andleft-hand contact of relay 24, the lower winding of relay 23 from thebattery connected to the break contact of relay 25. The current flowingthrough the lower winding of relay 23 is suiiicient to overcome thebiasing current and to operate relay 23 to its lefthand contact. Thisgrounds line I9 and repeats the signal impulse to the relay equipment I4con- -nected thereto.

follow the signal impulses, but rather keeps the battery disconnectedfrom the windings of relays 24 and 25 during the time signal impulsesare being received from lead 29 and retransmitted to lead I9. Thus, ifduring this time, ground is connected to lead I9, by the relay equipmentI4 connected thereto, due to some extraneous disturbance arising on theline I3 to which lead I9 is connected, relays 24 and 25 will not beoperated to repeat this ground to lead 29 and thus to the common circuit33. This prevents momentary disturbances arising in the line associatedwith lead I9 of Fig. 2 from being repeated to and interfering with allof the other telegraph stations and lines connected to the system.

Relay 26, in operating, also connects the battery from its make contactthrough the lower winding of relay 21 and the right-hand contact ofrelay 23 to line I9. Now, if during the time relay 25 is operated, dueto transmission of signals from lead 29 to lead I9, a ground isconnected to lead I9 by the associated relay equipment I4 due to somemomentary disturbance arising in the line connected to the associatedrelay equipment I 4, then a circuit will be completed from this groundconnected to lead |9 through the armature and right-hand contact ofrelay 23 and lower winding of relay 21 to battery through the makecontacts of relay 26. Current ilowing in this circuit causes relay 21 tobe operated. Relay 21, in operating, opens the ciry upper make contactsand winding of relay 21 to Y ground connected to lead I9 in theassociated relay equipment I4 to which lead I9 is connected. Relay 21also closes the operating circuit for relay 29 from battery through theoperated make contact of relay 26, upper winding of relay 29 to groundon the lower make contacts of relay 21. In addition, relay 21 inoperating opens the upper break contacts of its lower set of contacts.'I'his opens the operating circuit of message register 3| and thelocking circuit of relay 29 so that message register 3| cannot operateat this time. In case the ground connected to lead I9 in the connectedrelay equipment I4 is due to a momentary condition such as strayinterference and the like, relay 21 will release at the end of thedisturbance during the next marking interval of relay 23 before relay 26releases. When relay 21 thus releases before relay 26, it againcompletes the operating circuit of relay 26 through its upper breakcontact and also the operating circuit of message register 3| and holdinected to both terminals of the lower winding of relay 29 thus shuntingthe holding circuit of this relay and allowing the relay to releasewhich in turn allows message register 3| to release so Vthat relays 21and 29 and message register 3| are now returned to the original positionand ready to respond to and record further momentary disturbancesarising in the line to which Ylead I9 is connected.

Assume now that station I9 connected to line I9 of Fig. 2 through thecorresponding equipment |4 desires to transmit a break signal during thetime that it is receiving signals from some other station II) throughthe common circuit 33. Under this condition, as before, relay 23 repeatsthe signals received from the line 2U to line I9 and thus to the stationI connected to line I9 through the equipment I4 as shown in Fig. l.Relay 26 is also operated so that it has connected battery through thelower Winding of relay 21 to the right-hand Contact of relay 23 and hasdisconnected battery through the windings of relays 24 and 25 from thiscontact. rIhen, when station Il) receiving repeated message signalstransmits a break signal to the relay equipment I4 connected to itsline, this equipment i4 grounds conductor I9. As before, relay 2loperates opening the circuit of relay 26 and locking to the ground onconductor i9. Relay 2l also operates relay 29 and opens the operatingcircuit of message register 3l as before. In this case, the break signaltransmitted from station ID is s uiiiciently long to allow relay 26 torelease at which time relay 29 is released Without operating messageregister 3l because relay 26 removes the battery which operates andholds relay 29 operated. Relay 26, in releasing also connects battery tothe windings of relays 24 and 25 causing these relays to operate. groundto lead 2! and thus repeats the break signal received over lead I9 fromthe associated station lil to all the other stations of the system.

Thus, message register 3l records all the momentary circuit disturbancesarising in the line associated with lead I9 during the time that signalsare being transmitted to this lead and line, but does not record a longbreak signal transmitted from this line over iine i9 to the remainder ofthe stations of the system. lin addition, the relays prevent thetransmission of these short stray interfering impulses to the remainderof the system, but do not prevent transmission of long break signalimpulses.

A similar set of relays is shown associated with lead 2l) which operatein a manner similar to.

those described with reference to lead i9. In case it is desired to usemore than one of these protection units in a given system, certain ofthese relays may be omitted in all but one of the auxiliary equipments4since it is unnecessary to record more than once all. the momentarycircuit disturbances of the common circuit.

The foregoing speciiic embodiment oi this inventicn is for the purposeof clearly describing and illustrating this invention, the novelfeatures of which are set forth in the appended claims.

What is claimed is:

1. An impulse repeater comprising a first circuit, a second circuit,relays for repeating impulses from one of said circuits to the other ofsaid circuits, auxiliary relays for preventing certain of said repeatingrelays from repeating momentary stray impulses during the tim-e theother of saidrepeating relays are repeating impulses, a recordingmechanism for recording the number of momentary stray impulses receivedby said repeating relays during the repetition of signal impulses by theother of said repeating relays, and circuit connections between saidrecording mechanism, auxiliary relays and repeating relays for repeatingthe long impulses received by any oi said repeating relays during thereception of signal impulses by any other of said receiving relays, andadditional circuit connections for preventing the recording oi longimpulses as momentary stray impulses.

Relay 24, in operating, connects 2. A repeating system comprising morethan two line circuits, a relay circuit connected toeach of said linecircuits, an impulse transmitting circuit common to all of said relaycircuits for receiving signal impulses from any of said line circuitsand transmitting the received impulses to all the other line circuits,another relay circuit connected between said common circuit and one ofsaid relay circuits which comprises means for preventing thetransmission of momentary stray impulses between said common circuit andsaid relay circuit in a direction opposite to the direction of thetransmission of signal impulses, and means `for recording the number ofsuch momentary stray impulses received by the respective circuits.

3. A telegraph repeating system for repeating telegraph signal impulsesbetween a plurality of different types of telegraph systems comprising acommon impulse transmitting circuit, relay equipments connected to eachof said telegraph systems for transmitting impulses between said systemsand said common circuit, one of said relay equipments connected betweeneach of said telegraph systems and said common impulse circuit, anauxiliary relay equipment comprising a plurality of slow-acting relaysfor preventing the transmission of momentary disturbances through saidauxiliary equipment during the time signal impulses are beingtransmitted in the reverse direction, other means for recording thenumber of said momentary disturbances, and further circuit means fortransmitting long break signal impulses through said auxiliary relayequipment in both directions at all times and circuit means forpreventing the recording of said long signal impulses as momentarycircuit disturbances.

4. An impulse repeater comprising a rst circuit, a second circuit,relays for repeating impulses from either of said circuits to the otherof said circuits, additional relay equipment for counting and recordingonly the number of momentary circuit disturbances arising in one of saidcircuits during the transmission of signals to that circuit from theother of said circuits, and circuit means including said additionalrelay equipment for preventing said means from counting and recordinglong signal impulses as momentary circuit disturbances.

5. An impulse repeater comprising a first circuit, a second circuit,relays for repeating impulses from either of said circuits to the otherof said circuits, auxiliary relays for preventing the repetition ofmomentary circuit disturbances from either of said circuits during thetransmission of signal impulses to that circuit from the other of saidcircuits, and additional circuit means including slow-acting relays forpreventing the recording of long signal impulses as momentary circuitdisturbances.

6. An impulse repeater comprising a first circuit, a second circuit,relays for repeating impulses from either of said circuits to the otherof said circuits, additional relay equipment responsive solely tomomentary circuit disturbances arising in one oi said circuits duringthe repeating of impulses to that circuit from the other of saidcircuits, and means for counting and recording the number of saidmomentary circuit disturbances.

FULLERTON S. KINKEAD.

